[PVE-User] Analysis of free space...

[Alwin Antreich]

On 24 September 2025 18:29:26 CEST, Marco Gaiarin <gaio at lilliput.linux.it> wrote:
>Mandi! Marco Gaiarin
>  In chel di` si favelave...
>
>> Uh, wait... effectively we forgot to enable 'discard' on volumes, and we have
>> enabled afterward (but rebooted the VM).
>> I'll check refreservation property and report back.
>
>No, volumes seems have all refreservation to 'none', as expected; current
>situation is:
>
> root at lamprologus:~# zfs list | grep ^rpool-data
> rpool-data                  54.2T  3.84T   171K  /rpool-data
> rpool-data/vm-100-disk-0    1.11T  3.84T  1.11T  -
> rpool-data/vm-100-disk-1    2.32T  3.84T  2.32T  -
> rpool-data/vm-100-disk-10   1.82T  3.84T  1.82T  -
> rpool-data/vm-100-disk-11   2.03T  3.84T  2.03T  -
> rpool-data/vm-100-disk-12   1.96T  3.84T  1.96T  -
> rpool-data/vm-100-disk-13   2.48T  3.84T  2.48T  -
> rpool-data/vm-100-disk-14   2.21T  3.84T  2.21T  -
> rpool-data/vm-100-disk-15   2.42T  3.84T  2.42T  -
> rpool-data/vm-100-disk-16   2.15T  3.84T  2.15T  -
> rpool-data/vm-100-disk-17   2.14T  3.84T  2.14T  -
> rpool-data/vm-100-disk-18   3.39T  3.84T  3.39T  -
> rpool-data/vm-100-disk-19   3.40T  3.84T  3.40T  -
> rpool-data/vm-100-disk-2    1.32T  3.84T  1.32T  -
> rpool-data/vm-100-disk-20   3.36T  3.84T  3.36T  -
> rpool-data/vm-100-disk-21   2.50T  3.84T  2.50T  -
> rpool-data/vm-100-disk-22   3.22T  3.84T  3.22T  -
> rpool-data/vm-100-disk-23   2.73T  3.84T  2.73T  -
> rpool-data/vm-100-disk-24   2.53T  3.84T  2.53T  -
> rpool-data/vm-100-disk-3     213K  3.84T   213K  -
> rpool-data/vm-100-disk-4     213K  3.84T   213K  -
> rpool-data/vm-100-disk-5    2.33T  3.84T  2.33T  -
> rpool-data/vm-100-disk-6    2.28T  3.84T  2.28T  -
> rpool-data/vm-100-disk-7    2.13T  3.84T  2.13T  -
> rpool-data/vm-100-disk-8    2.29T  3.84T  2.29T  -
> rpool-data/vm-100-disk-9    2.11T  3.84T  2.11T  -
>
>and a random volume (but all are similar):
>
> root at lamprologus:~# zfs get all rpool-data/vm-100-disk-18 | grep refreservation
> rpool-data/vm-100-disk-18  refreservation        none                   default
> rpool-data/vm-100-disk-18  usedbyrefreservation  0B                     -
>
>Another strange thing is that all are 2TB volumes:
>
> root at lamprologus:~# cat /etc/pve/qemu-server/100.conf | grep vm-100-disk-19
> scsi20: rpool-data:vm-100-disk-19,backup=0,discard=on,replicate=0,size=2000G
>
>but:
>
> root at lamprologus:~# zfs list rpool-data/vm-100-disk-19
> NAME                        USED  AVAIL  REFER  MOUNTPOINT
> rpool-data/vm-100-disk-19  3.40T  3.84T  3.40T  -
>
>why 'USED' is 3.40T?
Snapshots by any chance?

Cheers,
Alwin

Hi Marco,